Apparatus and method for managing usage of a database system resources by concurrent database users of a database system

Abstract

An apparatus is provided for managing usage of database system resources by concurrent database users of a database system. The apparatus comprises a processor and a storage device communicatively coupled with the processor. The processor is programmed to (i) determine a number of in-use Access Module Processor Worker Tasks (AWTs) based upon at least one system-defined or user-definable Resource Limit rule, (ii) take a difference between the number of in-use AWTs and an AWT limit, and (iii) set the difference equal to a number of available AWTs for a new database job or request.

What is claimed is: 
     
         1 . An apparatus for managing usage of database system resources by concurrent database users of a database system, the apparatus comprising:
 a processor; and   a storage device communicatively coupled with the processor, wherein the processor is programmed to   (i) determine a number of in-use Access Module Processor Worker Tasks (AWTs) based upon at least one system-defined or user-definable Resource Limit rule,   (ii) take a difference between the number of in-use AWTs and an AWT limit, and   (iii) set the difference equal to a number of available AWTs for a new database job or request.   
     
     
         2 . An apparatus according to  claim 1 , wherein the processor is further programmed to
 (iv) calculate a number of in-use Access Module Processor Worker Tasks (AWTs) available for a new database job or request,   (v) estimate a number of AWTs required for a new database job or request to be started,   (vi) increment the number of in-use AWTs based upon at least one system-defined or user-definable Resource Limit rule when a new database job or request is starting, and   (vii) decrement the number of in-use AWTs based upon at least one system-defined or user-definable Resource Limit rule when an active database job or request is finishing.   
     
     
         3 . An apparatus according to  claim 2 , wherein at least one system-defined or user-definable Resource Limit rule is associated with one of database system resources such as spool space, memory, CPU usage, I/O usage, storage usage. 
     
     
         4 . An apparatus according to  claim 3 , wherein at least one system-defined or user-definable Resource Limit rule is associated with the database system resource of utilities and other database request types. 
     
     
         5 . An apparatus according to  claim 2 , wherein the processor is further programmed to
 (viii) decrement the number of in-use AWTs based upon at least one system-defined or user-definable Resource Limit rule when an active database job or request is transitioning into a new execution phase which needs less AWTs than current estimate.   
     
     
         6 . An apparatus according to  claim 5 , wherein at least one system-defined or user definable Resource Limit rule is associated with one of database system resources such as spool space, memory, CPU usage, I/O usage, storage usage. 
     
     
         7 . An apparatus according to  claim 6 , wherein at least one system-defined or user-definable Resource Limit rule is associated with the database system resource of utilities and other database request types. 
     
     
         8 . A method of managing usage of database system resources by concurrent database users of a database system, the method comprising:
 electronically by a processor, determining a number of in-use Access Module Processor Worker Tasks (AWTs) based upon at least one system-defined or user-definable Resource Limit rule;   electronically by a processor, taking a difference between the number of in-use AWTs and an AWT limit; and   electronically by a processor, setting the difference equal to a number of available AWTs for a new database job or request.   
     
     
         9 . A method according to  claim 8 , further comprising:
 electronically by a processor, calculating a number of in-use Access Module Processor Worker Tasks (AWTs) available for a new database job or request;   electronically by a processor, estimating a number of AWTs required for a new database job or request to be started; and   electronically by a processor, incrementing the number of in-use AWTs based upon at least one system-defined or user-definable Resource Limit rule when a new database job or request is starting; and   electronically by a processor, decrementing the number of in-use AWTs based upon at least one system-defined or user-definable Resource Limit rule when an active database job or request is finishing.   
     
     
         10 . A method according to  claim 9 , wherein at least one system-defined or user-definable Resource Limit rule is associated with one of database system resources such as spool space, memory, CPU usage, I/O usage, storage usage. 
     
     
         11 . A method according to  claim 10 , wherein at least one system-defined or user-definable Resource Limit rule is associated with the database system resource of utilities and other database request types. 
     
     
         12 . A method according to  claim 9 , further comprising:
 electronically by a processor, decrementing the number of in-use AWTs based upon at least one system-defined or user-definable Resource Limit rule when an active database job or request is transitioning into a new execution phase which needs less AWTs than current estimate.   
     
     
         13 . A method according to  claim 12 , wherein at least one system-defined or user-definable Resource Limit rule is associated with one of database system resources such as spool space, memory, CPU usage, I/O usage, storage usage. 
     
     
         14 . A method according to  claim 13 , wherein at least one system-defined or user-definable Resource Limit rule is associated with the database system resource of utilities and other database request types. 
     
     
         15 . A method according to  claim 8 , wherein the method is performed by a computer having a memory executing one or more programs of instructions which are tangibly embodied in a program storage medium readable by the computer. 
     
     
         16 . An apparatus for managing usage of computer system resources by concurrent database users of a computer system, the apparatus comprising:
 a storage device for storing a set of Resource Limit rules which are system-defined or user-definable and which allow an administrator to set resource usage limits based upon the set of Resource Limit rules; and   a processor for, based upon each rule of the set of Resource Limit rules, (i) incrementing a number which is indicative of an in-use resource based upon at least one system-defined or user-definable Resource Limit rule of the set of Resource Limit rules when a new computer job or request is starting, and (ii) decrementing the number which is indicative of an in-use resource based upon at least one system-defined or user-definable Resource Limit rule of the set of Resource Limit rules when a computer job or request is finishing or transitioning into a new execution phase and needing less resources.   
     
     
         17 . An apparatus according to  claim 16 , wherein the computer system comprises a database system. 
     
     
         18 . An apparatus according to  claim 17 , wherein the database system comprises a database system which uses a Service Level Goal (SLG)-driven workload management system. 
     
     
         19 . A method according to the apparatus of  claim 16 , wherein the method is performed by the processor having a memory executing one or more programs of instructions which are tangibly embodied in a program storage medium readable by the processor. 
     
     
         20 . A method according to the apparatus of  claim 17 , wherein the method is performed by the processor having a memory executing one or more programs of instructions which are tangibly embodied in a program storage medium readable by the processor.